I have the print out from the dyno rolling road tune-up undertaken by Aldon, in the West Midlands. An old school motorsport company that know what they are doing, especially when it comes to Twin Webber building, and tuning. They also do their own ignition systems. I will upload the print out once downloaded onto my computer.
Before I give the figures, I just want to say how important your coil is to power tune-ups. If you have a bad coil on its way out like I did, this alone will restrict your engine from running properly. For example, the car only showed 88bhp on the first run. The dyno tuner checked and tested everything. When he looked at the coil, it seemed to operate correctly up to a point. The coil test figures looked good with only a slight signal deviation on the computer monitor. The wet compression test showed that the engine was in very good health, but was still holding back. He first changed the spark plugs and leads, which improved things a bit, but the power figures still only showed 90bhp. Had he been an inexperienced technician, he may well have settled for that as the final state of tune. When the coil was tested on the meter for resistance the technician seem to suggest that he could not conclusively prove that the coil was at fault.
He changed the coil anyway for a new Lucas unit, but he did not seem happy when he tested the new coil unit on the meter to compare the reading with the old coil. At least, that's how it looked to me, due to the amount of time he spent on it. At this stage he had the car on the rollers for nearly 3 hours. After fitting the coil he gave the car another power run, and the readings surprised us all instantly. 159bhp was the reading as the team of 3 cheered on. He wanted to leave it there, but I asked him to have a quick look at the jettings and so forth to establish what the Twin 40 Webbers would max out at. Unfortunately, I could only afford a few more minutes of their time as the cost was looking close to £350 odd pounds. He changed the jets once, and gave the car another power run. 160bhp reading came up with 157lbs of torque. The torque curve is never ending, but the car can still potter around town, which seems odd to me.
The engineer said that the engine is more or less in a de-tuned state due to the exhaust being very restricted, and the lack of trumpets for the Webbers. He stated that by fitting a big bore free-flowing exhaust system, and having a look at porting out the exhaust manifold or having a stainless steel item made up. With a good set of trumpets for the Webbers, and time for testing different jets and and so forth, coupled with further ignition optimization, he would expect the car to be knocking on the door of 190bhp and loads more torque. I can tell you, the drive home was brutal .
